Telephone-exchange system and apparatus.



I. 662,966. Amuted 066. 4,1000. A. 6160613660.

TELEPHONE EXCHANGE SYSTEM AND APPARATUS.

fAppliction filed June 6, 1906.

(No Model.) 2 Sheets-Sheet l.

f1; Tl

c* S @d y we@ Nu. 662,986. Patented Dec; 4, lsoo.

v A, srnomena.

TELEPHGNE EXCHANGE SYSTEM AND APPARATUS.`

(Application led June 6, 1900.) Y

um Model.) 2 sheets-sheet 2.

l-lVEn ma? AIFELED E .taamnaacii www Nirnn STATESV ALFRED STROMBERG, OF CHICAGO,ILLINOIS.

TELEPHONE-EXCHANGE SYSTEM AND APPARATUS;

SPECIFICATION forming Apart of Letters Patent No. 662,986, dated December 4, 1900.

Application filed June 6, 1900. e'erialllo. 19,287. (No model.)

To all whom, it may concern:

Be it known that I, ALFRED STROMBERG, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Telephone -Exchange Systems and Apparatus, (Case No. 7,) of which the following is a full, clear, Concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to telephone-exchange systems and apparatus, and has 4for its object the provision of an improvedconstruction of switchboards involving an improved form and arrangement of spring-jacks, whereby a much larger number of spring-jackswitches may be assembled upon each section of board.

The inventionfurther contemplates an improved circuit arrangement of the operators apparatus and of the telephone-lines and line apparatus at the exchange, Wherebythe nu mberof switches may be reduced to a minimum, and whereby single-stranded-cord sets may be employed in completing connection between subscribers of metallic circuitlines. Heretofore two general forms and arrangements of spring-jacks have been employed. In one form and arrangement a vertically-arranged board provided with holes faced with metalbushings designed to receive connecting-plugs has been commonly employed, the switch-springs of the spring-jacks being disposed to the rear of the metal bushings or y thim bles in position to be engaged by inserted plngs,the switch-springs being mounted upon individual horizontally-disposed strips of insulating material mounted directly upon the rear of the aforesaid'vertical board. In early telephone practice this construction was adequate; but when the number of lines in a given exchange became vastly increased this construction of the prior art was insufficient to accommodate the increased number of multiple spring-jacks that should be provided upon each section of the switchboard. This structure of the prior art failed in this respect because of the great space required for the horizontally-arran ged sprin g supportingstrips.

Another arrangement and construction of the prior art consisted in the vertical board and individually-complete spring-jacks having metallic frames provided with thimble plug-receiving extensions inserted from the rear of the said vertical board in holes provided therein, This construction is also objectionable in that the metallic frames of the individnally-com plete jacks occupy considerable space both horizontally and vertically.

In accordance with myinvention I dispense with all horizontally-extending frames or supports for the springs and provide in place thereof a vertical support, which affords a mounting for a plurality of horizontal rows of springs, which may be' closely assembled vertically and horizontally, as this vertical support serves to merely anchor the springs in place. These springs constitute line connections of spring-jacks, a second vertical support being employed that constitutes the face of the switchboard-section, this second vertical support containing metallic testthimbles in the case of multiple boards from which metallic strips are extended toward the rear and anchored also at their rear ends in the same vertical support that carries the springs, these metallic strips acting as electrical connections for the test-thimbles and also serving to unite the two vertical supporting members to maintain the proper distance between the same to secure proper alinement of the thimbles with relation to the switch-springs of the multiple jacks and to form a firm integral structure.

By means of my invention I am enabled to employ a single line-spring in each springjack, whereby the construction is further simplied. Heretofore each operator has been provided usually with not more than live thousand line-jacks upon her section of multiple board. I have been enabled by means of my invention to provide each operators section of multiple board with about four times as many line spring-jacks, so that the capacity of the exchange may be greatly increased without enlargingthe space required for the apparatus.

I will describe my invention and addi-tional details fully by referring to the accompanying drawings, illustrating the preferred embodiment thereof, in which- Figure l is a front elevation of a switchboard constructed in accordance with my in- IOO vention. Fig. 2 is a plan view of a bank ofy banks, each bank constituting a unit, the.

banks being preferably arranged in vertical panels, three panels arranged side by side preferably constituting a section of the board. vIn practice I have been enabled to arrange the jacks afourth of an inch apart between centers both vertically and horizontally, and l prefer to assemble one hundred of these jacks in each bank, five rows of twenty jacks each being preferably contained in each bank. The front face orsupport A of insulating material of each bank contains the test-thimbles B, arranged in parallel rows. These test-thin] bles are provided with continuous rims at their front ends and with serrated rims at their rear ends. The teeth C' of the rear rims, Fig. 6, by being bent into engagement with the ring ends of the strip conductors C serve to mechanically and electrically unite the conductors C with the thimbles. A second vertical support Dis provided to the rear of the face A, the strip conductors C serving as distance-pieces to maintain the proper space between the supports A and D. In order that the conductors C may best serve this function, I provide the same with grooves C2 at their rear ends, as indicated clearly in Fig. 4, these grooves being of a length corresponding to the width of the support D, whereby said su pport by snugly fitting the said groove is prevented from having motion toward or from the support A. With the supports A and D thus relatively fixed the line-springs E may be secured to the supportD and held in proper position with relation to the thimbles. In order that the line-springs may be properly held in place, I also provide the rear or anchored ends thereof with grooves E', corresponding in length to the width of the support D. I preferably form the front support A of each bank in one integral piece of fiber, while the rear support D is preferably formed of as many horizontal strips of fiber as there are rows of jacks ineach bank, these strips of fiber being preferably provided with saw-cuts in which the strips Gand springs are received, the groove portions of the strips and springs preventing the longitudinal displacement of the springs and strips G with respect to the support D, while the saw-cuts prevent their lateral displacement. The spring-jacks are thus built in banks, which may be assembled vertically to form panels, as indicated in Fig. 1.

ceases An important feature of my invention con'- sists in the provision of improved means for wiring boards constructed as described, which feature may also be employed in connection with boards of other construction. Instead of providing the rear ends of the conductors C and E with holders for attachment of wire, the practice hitherto generally followed, I provide thel said ends with an open recess C2 in an edge of each of these conducting portions. By this means I am enabled to pass the line and test conductors back of the multiple-switchboard sections and to effect connections thereof with the conductors C and E without cutting the wire, but by merely forming loops G therein, the insulation being scraped away from the wire where it is to be soldered to the conductor, theloops being extended forwardly from the conduct-ors. I thus provide a very simple and effective Way of wiring the board without introducing a great number of joints or soldered connections as component parts of the conductors.

I preferably employ the system illustrated diagrammatically in Fig. 5, where I have illustrated a well-known form of telephone appliance, comprising a telephone-receiver H, transmitter I, together with the primary and secondary coils, a signal-bell K, and switchboard L. This telephone station is connected by means of metallic circuit M N with the several sections of the multiple board. The limbs N of each telephone-line extending along the board are preferably directly united at a common point, with which a pole of the common battery O is connected. The other pole of the' common battery is shown as connected to the cord-strand P, provided with terminal plugs Q Q, a clearingout drop R being included in the conductor connecting the com mon battery with the cordstrand. I have'not indicated the line-indicator in connection with the metallic circuit M N, as this forms no part of the present invention.

1 have illustrated an answering-jack S, in which the answering-plug may be inserted. By the arrangement shown a single linespring at each line-jack is only required; but in order that induction and cross-talk may be avoided the conductor M is provided with loops T, that extend parallel with the loops G, whereby this induction is counteracted. The loops G and T are preferably twisted, more effectively to secure the desired result. I

have indicated the loops G and T as being distinct, but they may be interwound if desired.

There are features of my invention that are capable of use in other systems vthan multiple-switchboard systems, particularly the manner of connecting the line conductors with the line-springs.

I have herein shown and particularly described the preferred embodiment of my invention, but I do not wish to be limited to the precise embodiment of the invention dis- IOO IIO

IZO

closed, as modifications may be made without departing from the spirit thereof; but,

Having thus described my invention, I

united thereby, a common battery connected in bridge at the exchange between the cordstrand and the directly-united limbs of the claim as new and desire to secure by Letters telephonedines, and an indicator in the same 7o Patentbridge with the battery; the limbs of the tele- 1. In a telephone exchange system, the phone-lines that are not permanently concombination with the limbs of a metallic-cirnected being each provided with a loop excuit telephone-line, ol` a line-switch provided tending to and connected with a line-switch on a switchboard, one limb of the line being atthe exchange, the directly-connected limbs io provided with a loop at said line-switch, which of the line being also provided with a loop exis connected with the said switch, the other tending parallel with the loop that is conlimb of the line being also provided with a nected with the switch to avoid induction, the loop at said line-switch, but free of direct consaid loops being twisted, substantially as denection with said line-switch, substantially as scribed; 8o 15 described. 5. In a telephone exchange system, the

i 2. In a telephone exchange system, the combination with a plurality of metallic telecombination with the limbs of a metallic-cirphone-lines extending to and from the excuit telephone-line, of a plurality of linechange, one limb of each of the metallic teleswitches provided on a switchboard, one limb phone-lines being connected directly together 2o of each line being provided withaloop at, and at the exchange, independently of cord conconnected with, each of said line-switches, the necting apparatus, of a single cord-strand proother limb of the line being also provided with vided with suitable connecting means adapta loop at each line-switch, but free of direct ed to connect the remaining limbs of the meconnection therewith, the said loops being tallic-circnit telephone-lines,atelephouic cir- 9o 25 twisted, substantially as described. cuit between the subscribers thereby com- 3. In a telephone -exchange system, the prising the limbs of the metallic lines that combination with a plurality of metallic teleare directly connected at the exchange, and phone-lines extending to and from the exthe single cord-strand with the remaining change, one limb of each of the metallic telelimbs united thereby, a common battery con- 3o phone-lines being connected directlytogether nected with the directly-united limbs of the at the exchange, independently of cord conmetallic lines, and with the cord-strand and necting apparatus, ofasingle cord-strand proan indicator in the circuit with the battery vided with suitable con neet-ing means adaptand cord-strand; the limbs of the telephoneed to connect the remaining limbs of the melines being each provided with a loop, aswitch 10o 3 5 tall'ic-circuit telephone-lines, a telephonie circonnected with one ot' the loops of each line, cuit between the subscribers thereby compristhe companion loop of the directly-connected ing the limbs of the metallic lines that are limb extending parallel with the aforesaid directly connected at the exchange, and the loop that is connected with the switch to avoid single cord-strand with the remaining limbs induction, the said loops being twisted, sub- 4o united thereby, a common battery connected stantially as described.

in bridge at the exchange between the cord- 6. In a telephone -exchange system, the strand and the directly-united limbs of the combination with a plurality of telephonetelephone-lines, and an indicator in the same lines extending from subscribers stations to bridge with the battery; the limbs ofthe telean exchange, one limb of each of the lines be- 11o 45 vphone-lines that are not permanently coning permanently connected together at the nected being each provided with a loop exexchange independently of cord connecting tending to and connected with a line-switch apparatus, of a single cord-strand provided at the exchange, the directly-connected limbs with a single connecting means adapted to of the line being also provided with a loop exconnect the remaining limbs of the lines, the

5o tending parallel with the loop that is contelephonie circuit between the subscribers nected with the switch to avoid induction, thereby comprising the limbs of the lines that substantially as described. are directly connected at the exchange and 4. In a telephone exchange system, the the single cord-strand with the remaining combination with a plurality of metallic telelimbs united thereby, and line-switches con- 12o 55 phone-lines extending to and from the exnected with limbs that are connected through change, one limb of each of the metallic telethe agency of the cord-strand, the limbs of phone-lines being connected directlytogether the lines extending along the switchboard, at the exchange, independently of cord conthe said limbs being provided with parallel necting apparatus,ofasinglecord-strand proloops, the loops of the permanently-united 6o vided with suitable connecting means adaptlimbs being free of direct connection with the ed to connect the remaining limbs of the meline-switches, while the loops of theremaining tallic-circuit telephone-lines, a telephone-cirlimbs have direct connection with the linecuit between the subscribers therebycomprisswitches, the said loops coperating to preing the limbs of the metallic lines that are vent cross-talk, substantially as described. 13o

65 directly connected at the exchange, and the 7. In a switchboard, the combination with single cord-strand with the remaining limbs a front vertical support formed in one integral piece provided with a plurality of horizontal rows of plug-openings, of a rear vertical support united to the aforesaid support, and a plurality of rows of line-springs mounted in the rear Vertical support contiguous to the said openings, whereby the plug-openings may be brought closer together vertically as well as horizontally, substantially as described.

8. In a multiple switchboard, the combination with a front Vertical support formed in one integral piece provided with a plurality of horizontal rows of test-thirnbles,'of a rear vertical support, a plurality of rows of linesprings mounted in the rear vertical support `contiguous to the said thiinbles, and conductors C attached to the test-'thimbles and engagin g the rear vertical support, whereby the said conductors C aot to vunite the vertical supports and at the same time convey ourrent to the test-thimbles, substantially as described. A

9. In a multiple switchboard, the combination with a front Vertical support provided with a plurality of horizontal rows of testthilnbles, of a rear Vertical support, a plurality of rows of line-springs mounted in the rear vertical support contiguous to the said thimbles, and conductors C attached to the testthimbles and engaging the rear vertical sup` port, whereby the said conductors C aot to unite the vertical supports and at the same time convey current to the test-thimbles, substantially as described.

In witness whereof I hereunto subscribe my naine this 14th day of May, A. D. 1900.

ALFRED STROMBERG. Witnesses:

GEORGE L. CRAGG, IIERBERT F. OBERGFELL. 

